In complex systems, such as automobiles, multiple modules can be used to monitor and/or control various operating parameters and to communicate data related to those operating parameters to an ECU, which may control various components and provide outputs to a dashboard or display. Conventionally, such modules can be connected using a hub-and-spoke or star-type connection scheme where the ECU is connected to each module through a dedicated line or bus. Unfortunately, the sensor wiring adds to the wiring complexity and overall cost of the system. Further, each dedicated line or bus represents at least two potential failure points where the line is connected to the ECU and where the line is connected to the module.
Alternatively, each of the modules can be connected to the ECU through a common bus. Examples of such an architecture include the Controller-Area Network (CAN)-bus, which is a vehicle bus standard designed to allow microcontrollers and devices to communicate with each other within a vehicle without a host computer. CAN-bus defines a message-based protocol (designed specifically for automotive applications but now also used in other areas such as industrial automation and medical equipment) that is sent via differential signals. Another example includes the Local Interconnect Network (LIN)-bus, which is a vehicle bus standard or computer networking bus-system used within current automotive network architectures that uses single-ended communications. The LIN-bus is a small and slow network system that is used as a cheap sub-network of a CAN-bus to integrate intelligent sensor devices or actuators. While common bus architectures, such as CAN-bus or LIN-bus, are typically more reliable than hub-and-spoke or star-type topologies because they have fewer failure points, each module needs to be assigned a unique address for the common bus to operate.
In the following discussion, the same reference numerals are reused within the figures to indicate the same or similar elements.